Light-erasable embedded memory device and method of manufacturing the same

Abstract

A light-erasable embedded memory device and a method for manufacturing the same are provided in the present invention. The light-erasable embedded memory device includes a substrate with a memory region and a core circuit region, a floating gate on the memory region of the substrate, at least one light-absorbing film above the floating gate, wherein at least one light-absorbing film is provided with dummy via holes overlapping the floating gate, and a dielectric layer on the light-absorbing film and filling up the dummy via holes.

What is claimed is: 
     
       1. A light-erasable embedded memory device, comprising:
 a substrate with a memory region and a core circuit region; 
 a floating gate on said memory region of said substrate; 
 at least one light-absorbing film above said floating gate over said memory region and said core circuit region, wherein at least one said light-absorbing film is provided with a plurality of dummy via holes overlapping said floating gate; and 
 a dielectric layer on said light-absorbing film and filling up said dummy via holes. 
 
     
     
       2. The light-erasable embedded memory device of  claim 1 , wherein said dummy via holes are arranged in an array. 
     
     
       3. The light-erasable embedded memory device of  claim 1 , wherein the material of said light-absorbing film is silicon oxynitride (SiON) or silicon nitride (SiN) with relatively low transmission coefficient for UV light. 
     
     
       4. The light-erasable embedded memory device of  claim 1 , further comprising an ultra thick metal on said core circuit region of said substrate, wherein said ultra thick metal forms in said light-absorbing film and said dielectric layer. 
     
     
       5. The light-erasable embedded memory device of  claim 1 , wherein the material of said dielectric layer is fluorosilicate glass (FSG). 
     
     
       6. The light-erasable embedded memory device of  claim 1 , wherein said memory region is a one-time programming (OTP) region. 
     
     
       7. A method of manufacturing a light-erasable embedded memory device, comprising steps of:
 providing a substrate with a memory region and a core circuit region; 
 forming a floating gate on said memory region of said substrate; 
 forming at least one light-absorbing film above said floating gate over said memory region and said core circuit region; 
 forming a plurality of dummy via holes and via holes concurrently in said light-absorbing film respectively above said memory region and said core circuit region, wherein said plurality of dummy via holes overlap said floating gate on said memory region; and 
 forming a dielectric layer over said light-absorbing film and filling up said dummy via holes and said via holes. 
 
     
     
       8. The method of manufacturing a light-erasable embedded memory device of  claim 7 , further comprising a step of performing an etch process on said core circuit region to form a recess in said light-absorbing film and said dielectric layer. 
     
     
       9. The method of manufacturing a light-erasable embedded memory device of  claim 7 , further comprising a step of filling up said recess in said light-absorbing film and said dielectric layer with metal material to form a metal layer. 
     
     
       10. The method of manufacturing a light-erasable embedded memory device of  claim 9 , wherein said metal layer is an ultra-thick metal (UTM). 
     
     
       11. The method of manufacturing a light-erasable embedded memory device of  claim 7 , further comprising a step of irradiating UV light passing through said dummy via holes and reaching said floating gate to erase storage data. 
     
     
       12. The method of manufacturing a light-erasable embedded memory device of  claim 7 , wherein said memory region is a one-time programming (OTP) region. 
     
     
       13. The light-erasable embedded memory device of  claim 1 , wherein said at least one light-absorbing film comprises a plurality of said light-absorbing films, and each said light-absorbing films is provided with a plurality of dummy via holes completely overlapping said dummy via holes of other said light-absorbing films and said floating gate. 
     
     
       14. The method of manufacturing a light-erasable embedded memory device of  claim 7 , wherein said at least one light-absorbing film comprises a plurality of said light-absorbing films, and each said light-absorbing films is provided with a plurality of dummy via holes completely overlapping said dummy via holes of other said light-absorbing films and said floating gate.